1. Field of the Invention
The present invention relates to a lens protector for protecting a lens, which is mounted on a camera and the like.
2. Description of the Related Art
In a camera wherein a barrier for a lens protection is mounted at a cabinet side, there is adopted a measure for saving space in which a two-bladed structure of barrier is provided so that the barrier is stored on a superposition basis or is saved separately at the right and left. However, according to the prior art, there is provided such an arrangement that the barrier is moved in a horizontal direction. This structure needs a large number of parts such as racks, pinions, levers and the like. Accordingly, it takes a large cost and needs a corresponding space for storing those parts.
For example, there is known a technology (Japanese Utility Model Registration No. 2593878) which relates to a plurality of movable barrier units opening and closing in a direction perpendicular to an optical axis with respect to a lens aperture of a lens barrel cover top portion, wherein there are provided a travelling direction rack, a gear engaging with the rack, a driving rack, and an operational member. This technology is suitable for a small and light type of camera, since it simply needs a small mounting space and a little number of parts. However, according to this technology, the rack moves to a projecting position at the time of the opening of the lens aperture, and thus this technology is not sufficiently suitable for compactness. Further, this technology needs a large number of parts such as a plurality of racks, pinions and gears.
Further, there is known a barrier unit comprising two-divided barriers, a connecting lever for connecting those barriers with one another, a holding section for holding the barriers at an opening position or a closing position, and a receiving plate forming a travelling space, wherein a geometry of the two-divided barriers and the receiving plate is a part of a spherical shell having the same spherical center (cf. for example, Japanese Patent Application Laid Open Gazette Toku-Kai Hei. 5-216092 (paragraph 0007)). This barrier unit is simple in structure and does not have many parts, and is compact. Further, this barrier unit is effective to prevent erroneous stop of the barrier and also to stably hold the barrier at the opened position. Thus this barrier unit has a high operability, durability and functional ability. According to this barrier unit, the barrier moves horizontally, and is a manual operating unit. And thus this barrier unit needs parts such as a link and a return spring, and thereby needing a large space in a horizontal direction.
In view of the foregoing, it is an object of the present invention to provide a lens protector, which is simple in structure and contributes to saving a space.
To achieve the above-mentioned objects, the present invention provides a lens protector that covers a lens aperture of a cabinet on an open and close basis, wherein the lens protector has a lens-protecting barrier consisting of two barrier blades, which are rotatably mounted around one shaft to cover the lens aperture on a sharing basis, and are superposed upon each other when saved from the lens aperture.
According to the lens protector of the present invention as mentioned above, a two-blade barrier is driven in accordance with a coaxial revolving system. This feature makes it possible to contribute to simplifying the structure of the device and thereby reducing the number of parts.
In the lens protector according to the present invention as mentioned above, it is preferable that the cabinet has a revolving guide that guides a revolution of one of the two barrier blades. Here, it is also preferable that said one barrier blade has a revolving guide that guides a revolution of another barrier blade.
This feature makes it possible to implement providing of two blades of the barrier, even if the barrier has geometry that the barrier drops out from the guide of the cabinet. Thus, according to the present invention, it is possible to provide a barrier mechanism advantageous in cost and space.
In the lens protector according to the present invention as mentioned above, it is preferable that the two barrier blades consist of a half moon shaped barrier blade that covers a part of the lens aperture and another barrier blade of a wane portion.
In the lens protector according to the present invention as mentioned above, it is preferable that the lens protector further has a driving device that causes the two barrier blades to revolve around the shaft.
This feature makes it possible to automatically open and close the barrier blades.